Electrical connector cluster assembly



Oct. 3, 1967 A. LOOKE ELECTRICAL CONNECTOR CLUSTER ASSEMBLY Filed Aug.20. 1965 INVENTOR ATTORN WITNESSES $2MM J Arvo Looke United StatesPatent 3,345,605 ELECTRICAL CONNECTOR CLUSTER ASSEMBLY Arvo Looke,Columbus, Ohio, assignor to Westinghouse Electric Corporation,Pittsburgh, Pa., a corporation of Pennsylvania Filed Aug. 20, 1965, Ser.No. 481,255 Claims. (Cl. 339-192) ABSTRACT OF THE DISCLOSURE Apparatusespecially adapted for connecting a hermetic compressor motor to thehermetic shell mounted terminal of the type having three closely spacedpins with flat tabs thereon, the cluster assembly including a block withcavities therein in an orientation in which the contact sockets arerelatively flat and disposed at equilateral angles with each other toalign with the tabs on the pins, with the cavities including a troughfor the'contact wires and ferrules to extend directly to the edge of theblock and emerge in a pin wheel array, with the thoughts passing nocloser to an adjacent terminal than the spacing between the pin-tabsthemselves.

This invention relates to an electrical connector of the character inwhich the terminal ends of the group of electrical conductors are heldin assembled relation for making aganged electrical connection with aseries of correspondingly arrayed pin terminals.

While the connector cluster according'to the invention may be used withvarious electrical devices, one immediate application is for connectinga refrigerant compressor motor to the terminal pins projecting through ahermetically sealed shell. Accordingly, such an arrange ment will .beused as an example for descriptive purposes.

An electrical connector cluster assembly for such use should berelatively small and of low profile, relatively inexpensive, easilyhandled and oriented within the limited space between the shell andother interior components of the shell, and arranged to preventelectrical shorts between the separate terminals.

Accordingly, an object of this invention is the provision of anelectrical connector cluster assembly which poss'esses these features aswell as others to be later noted herein. a

An appreciation of the nature of the invention may be aided byexplainingin somewhat more detail the environment in which an assemblyaccording to the invention is found particularly useful. Small hermeticcompressors of a size used in domestic refrigerators, freezers, airconditioners, and such products are mass produced'for incorporation inmillions of such appliances each year. A number. of manufacturers ofsmall hermetic compressors use a standard hermetic terminal whichcarries three pin Conductors .in sealed and insulated relation throughthe shell of the. hermetic compressor. Since these hermetic therminalsare mass produced by one or two suppliers for the most part, the unitcost is relatively low. One such standard hermetic terminal is made bythe Fusite Corporation and has three internally-projecting pins arrangedas if they were at the corners of a substantially equilateral triangleand with the axes of adjacent pins being less than a half inch from eachother. One typical way of connecting the leads of the compressor motorto the pins has been to push each connector individually onto itsrespective pin. Making the individual connections is quite timeconsuming and also increases the chance that two or three of theconnectors may be connected to the wrong pins. While cluster assembliesfor making ganged connections are well known, the. structuralarrangement the description of the cavity which is shaped to receive3,345,605 Patented Oct. 3, 1967 according to this invention provides anumber of advantageous features with respect to the relatively smallhermetic terminal of a standard nature With which it is used.

In accordance with the invention, a mounting block is provided with anumber of connector cavities for holding the connectors in a properarray to fit the hermetic pins. The connectors are formed to beaccommodated by the cavities, with these cavities being arranged so thateach conductor emerges from the edge of the mounting block at a locationclosely adjacent the connector. Preferably, the outline shape of themounting block is generally triangular, and the space to accommodateeach of the connector ferrules generally cuts across a corner of thetriangular shape so that the conductors emerge from the edge of theblock along a line forming an acute angle with one adjacent side of theblock. This facili tates wrapping the conductors around the edge of theblock in closely hugging relation to a location where they are fastenedtogether into a group. This arrangement lends itself to the clusterassembly having a natural orientation which can be used to insurecorrect connec tions.

The invention will be described in more detail in connection with theaccompanying drawings illustrating two embodiments thereof by way ofexample, and wherein:

FIGURE 1 is a plan view of the rear (i.e., cover) side of a clusterassembly according to the invention;

FIG. 2 is a plan view of the rear side of the mounting block with thecover removed and the connectors omitted;

FIG. 3 is a sectional view corresponding to one taken along the lineIII-III of FIG. 2 but with a connector installed in its cavity;

FIG. 4 is a fragmentary isometric view of one corner of the mountingblock, with a connector for the cavity in that corner shown in explodedrelation to the block;

FIG. 5 is an elevational view of a portion of the inside face of ahermetic compressor shell provided with a hermetic terminal havinginwardly projecting terminal pins to which the cluster assembly, shownbelow the hermetic terminal and in unconnected relation, is to beconnected; and

FIG. 6 is a fragmentary isometric view of a portion of a mounting blockprovided with a modified cavity configuration, and with a connector alsohaving a modified configuration so as to mate with the cavity of theblock shown in exploded relation.

The cluster assembly is shown in FIG. 1 in its assembled form with threeelectrical conductors 10, 12 and 14 emerging from three underlyingcavities 15 at peripherally-spaced locations about the edge of thegenerally triangular insulating block 16. The lead wires 10 and 12 arewrapped around the peripheral edge from their point of emergence to forma three wire group with the other conductor 14 adjacent the location ofthe lead wire 14. The three conductors are fastened together by anysuitable means such as the cord 17 at this emergence location of thewire 14, and the group then extends to be connected to the compressormotor (not shown).

I The cover 18 for the rear face of the block 16 is generallyhexagonally shaped and fits with three of the side edges 20 of the coverflush with the three corresponding edges of the block, and the otherthree edges 22 of the cover seating within the raised abutments 24 atthe cor ners of the block. The cover is conveniently fastened to theblock with a rivet or screw 26. Referring now to FIGS. 2-4, a cavitygenerally designated 15 is provided adjacent each corner of the block toreceive a connector 30 secured to the end of a motor lead wire. Theparts of the connector will be first identified (FIG. 4) to facilitateof emergence the connector. The connector includes a conventionallyshaped socket portion 32 adapted for a slip-on connection to a hermeticterminal pin, a ferrule portion 34 which is crimped onto the bare leadwire and adjacent insulating material of the conductor, and anintermediate web portion 36. The terminal shown in FIG. 4 has an initialshape before formation according to the invention of a flag terminal inwhich the axes of the ferrule and socket are perpendicular andintersecting. However, this form is changed by bending the web along aline parallel to the ferrule axis and adjacent the socket so that anacute angle is formed between the closed planar face of the socket andthe web. This shape will hereinafter be referred to a the saddle (also36) since the connector seats in saddle fashion upon a ridge in theblock cavity as will be noW described.

Each cavity (FIGS. 2-4) which receives a connector includes asocket-receiving opening 38 extending between the rear face 40 and thefront face 42 of the block, a ferrule receiving trough-shaped recess 44open at one end 45 to the edge of the block, and a wall 46 having itsedge 48 recessed below the rear face of the block. The trough 44 and theedge 48 generally cut across a corner of the triangular-shaped block inthis described embodiment of the cluster assembly, but only one end ofthe trough is open to the edge of the block.

The manner in which the terminal seats in the cavity is perhaps bestvisualized from FIGS. 3 and 4. The socket 32 fits in the opening 38, theferrule 34 lies in the trough 44 with its connected wire extending outof the open end 45 at the edge of the block, and the saddle 36 seats onthe edge 48. The opening, trough, and recessed edge are designed toallow a degree of freedom of movement of the connector in the cavity sothat the connector is essentially self-aligning with the pins on whichit is pushed to make the connection.

The orientation of the cavities in the embodiment thus far described issuch that the lead wires emerge from the edges of the block in what mayaptly be termed pinwheel fashion. As such, the lead wires emerge atacute angles relative to adjacent edges of the block so that theflexible leads may be wrapped easily about the edge without departingvery far from the edge. As shown in FIG. 1, the wires 10 and 12 arewrapped about the edge and are collected to form a group with wire 14near the place where it emerges from the edge of the block. Here thethree wires are tied together by a piece of string or the like. Theleads typically used with a cluster assembly for the exemplaryapplication are of the character that when the three leads are tiedtogether, the cluster assembly and wire portions closely adjacent thecluster assembly are conveniently handled as a more or less integralunit. Also, as will be explained in connection with FIG. 5, with thethree leads tied together closely to the edge of the block, the blockhas a natural position which facilitates the correct connection of thecluster assembly to the hermetic terminal.

The hermetic terminal 50 in FIG. 5 has three equilaterally spaced posts,each of which comprises a pin 52 and a tab 54 welded thereon, with theterminal base sealed to the wall 56 of the compressor. With the motorends (not shown) connected to the motor, and with the length of theleads being restricted to a length which only permits the clusterassembly to reach the hermetic terminal, the cluster assembly cannot beincorrectly connected. Specifically, rotation of the cluster assembly ofFIG. 5 from its illustrated position is resisted by the conductors beingtoo short to easily accommodate a 120 rotation of the cluster assemblyin either direction and still reach the terminal. Of course, by havingthe conductors tied together, this also can serve as in indication ofproper orientation. That is, the assembler need simply remember that thewires are to be on the bottom, for example.

While the presently preferred embodiment for commercial purposes is asshown in FIGS. 1-5, an alternative embodiment having a structure asshown in FIG. 6 may sometimes be desirable. In this case, the connectorgenerally designated 60, and the cavity generally designated 62, arearranged so that while the socket 64 has the same orientation in thecluster, the ferrule 66 extends radially outwardly from the socket. Inthis arrangement, the trough 68 has been turned from its FIGS. 1-5disposition, and the connector is correspondingly formed to fit it. Inother respects the construction of the components is similar to thefirst described embodiment in that the terminal includes a saddle 72,and the opening and trough of the cavity are sufficiently large topermit selfalignment when the cluster assembly is pushed onto theterminal posts. In the FIG. 6 embodiment, the leads are also wrappedaround the edge of the block to form a common group at the point ofemergence of one of the wires.

Partly by way of summary, it will be appreciated from the foregoingdescription that a cluster assembly according to the invention providesan arrangement in which the contact sockets may be closely spacedtogether to mate with a standard hermetic terminal having closely spacedposts, but in which the lead wires connected to the contact sockets arenot required to pass in close proximity to any of the other contactsockets or other metallic parts of the terminal. At the same time, themounting block and terminals are so disposed that the thickness of thecluster assembly is held to a small value so that the cluster assemblymay be manipulated within the relatively limited space within thecompressor shell. Further, terminals may be used which are convenientlyavailable as standard terminals and need only be bent to provide a shapeconforming to the particularly shaped cavitie in the mounting block.

I claim as my invention:

1. A cluster assembly for making a gang connection to a plural postterminal of the type including equilaterally spaced pins carryingequi-angullarly oriented tabs thereon tangent to the radially outer sideof each of the pins, said cluster assembly comprising:

a mounting block having opposite front and rear faces;

a number of individual electrical connector terminals carried by saidblock in a predetermined orientation, each terminal including arelatively flat contact socket to fit on said pin-tabs, a wire-grippingferrule, and an intermediate web;

said block including means defining a cavity to accommodate each of saidterminals, said cavities being spaced radially outwardly from thecentral portion of said block;

each of said cavities including a radially-inner,socketreceiving-opening extending between said opposite faces toaccommodate said socket with the socket major dimension extendingtangent to the circle passing through said pin-tabs, and an adjacent,radially-outer trough to accommodate said ferrule, said trough extendingrelatively directly to the edge of said block to provide an opening forthe emergence of the wire gripped by said ferrule in the immediatevicinity of said cavity, said trough extending to said block edges in apath in which it does not pass more closely to any adjacent terminalcavity within the peripheral limits of said block than the spacingbetween adjacent terminals, said intermediate web being bent to form anacute angle between said ferrule and contact socket so that said ferruleoccupies a level in said trough within the length of said contactsocket.

2. A cluster assembly for making a gang connection to a plural postterminal of the type including equilaterally spaced pins carryingequi-angularly oriented tabs thereon tangent to the radially outer sideof each of the pins, said cluster assembly comprising:

a mounting block having opposite front and rear faces;

a number of individual electrical connector terminals carried by saidblock in a predetermined orientation,

each terminal including a relatively flat contact socket to fit on saidpin-tabs, a wire-gripping ferrule, and an intermediate web;

said block including means defining a cavity to accommodate each of saidterminals, said cavities being spaced radially outwardly from thecentral portion of said block;

each of said cavities including a radially-inner,socketreceiving-opening extending between said opposite faces toaccommodate said socket with the socket major dimension extendingtangent to the circle passing through said pin-tabs, and an adjacent,radially-outer trough to accommodate said ferrule, said trough extendingrelatively directly to the edge of said block and being open thereat toaccommodate the emergence of the wire gripped by said ferrule, saidtrough extending to said block edges in a path in which it does not passmore closely to any adjacent terminal cavity Within the peripherallimits of said block than the space between adjacent terminals, saidintermediate web being bent to form an acute angle between said ferruleand contact socket so that said ferrule occupies a level in said troughwithin the length of said contact socket, all of said troughs beingdisposed relative to each other so that said wires emerge from said edgeof said block in a pin-wheel array.

3. The cluster assembly of claim 2 wherein:

said block has a generally triangular outline shape,

and said troughs extend in a direction generally cutting the corners ofsaid triangular shape.

4. A cluster assembly according to claim 2 wherein:

said wires are wrapped around the edge of said block in closely huggingrelation thereto to form a group at the location of emergence of one ofsaid wires; and

means are provided to fasten said group together at said emergencelocation of said one wire.

5. A cluster assembly according to claim 2 wherein:

each of said cavities includes a wall between said socket opening andsaid trough, the edge of said wall adjacent said rear face of said blockbeing recessed; said socket and said Web are bent toward each other toform a saddle adapted to seat upon said wall.

6. A cluster assembly according to claim 5 wherein:

each said socket opening and said trough are oversized relative to saidsocket and said ferrule to provide a loose fit so that said terminal issubstantially self-aligning upon connection to a mating part.

7. A cluster assembly for making a gang connection to a plural postterminal of the type including equilaterally spaced pins carryingequi-angularly oriented tabs thereon tangent to the radially outer sideof each of the pins, said cluster assembly comprising:

a mounting block having opposite front and rear faces;

a number of individual electrical connector terminals carried by saidblock, each terminal including a relatively flat contact socket to fiton said pin-tabs, a Wire-gripping ferrule, and an intermediate Web, saidterminal being shaped to provide a saddle in said Web between saidsocket and said ferrule;

a cavity for each terminal in said block, each said cavity comprising anopening extending through said block from said rear to said front faceto accommodate a socket with the socket major dimension extendingtangent to a circle passing through said pintabs, a trough open to saidrear face and having one end thereof open to the edge of said block toaccommodate said ferrule, and a Wall between said opening and saidtrough to receive said saddle-formed Web;

said troughs extending to said block edges in a path in which they donot pass more closely to any adjacent terminal cavity Within theperipheral limits of said block than the spacing between adjacentterminal cavities, said troughs being located and disposed relative tothe center of said block that the wires gripped by said ferrules extendrelatively directly to and emerge through said block edge in apin-wl1eel array; and

a cover for said rear face of said block to hold said terminals in saidcavities.

8. A cluster assembly according to claim 7 wherein:

said block is generally triangular in outline;

said cavities are disposed with said troughs cutting the corners of saidblock.

9. A cluster assembly according to claim 8 wherein:

two of said wires are wrapped around said edge of said block to join thethird wire and form a collected group at the location of emergence ofsaid third mm.

10. A cluster assembly according to claim 9 wherein:

said cavities are equidistantly spaced from the center of said block.

References Cited UNITED STATES PATENTS 2,360,917 lO/1944 Wade 339-192 X2,556,956 6/1951 Benton et a1. 339193 2,563,775 7/1951 Del Camp 339-1933,227,910 l/l966 Pittman 339193 X MARVIN A. CHAMPION, Primary Examiner.

W. DONALD MILLER, Examiner.

I, R MOSES, Assistant Examiner,

1. A CLUSTER ASSEMBLY FOR MAKING A GANG CONNECTION TO A PLUAL POSTTERMINAL OF THE TYPE INCLUDING EQUILATERALLY SPACED PINS CARRYINGEQUI-ANGULARLY ORIENTED TABS THEREON TANGENT TO THE RADIALLY OUTER SIDEOF EACH OF THE PINS, SAID CLUSTER ASSEMBLY COMPRISING: A MOUNTING BLOCKHAVING OPPOSITE FRONT AND REAR FACES; A NUMBER OF INDIVIDUAL ELECTRICALCONNECTOR TERMINALS CARRIED BY SAID BLOCK IN A PREDETERMINEDORIENTATION, EACH TERMINAL INCLUDING A RELATIVELY FLAT CONTACT SOCKET TOFIT ON SAID PIN-TABS, A WIRE-GRIPING FERRULE, AND AN INTERMEDIATE WEB;SAID BLOCK INCLUDING MEANS DEFINING A CAVITY TO ACCOMMODATE EACH OF SAIDTERMINALS, SAID CAVITIES BEING SPACED RADIALLY OUTWARDLY FROM THECENTRAL PORTION OF SAID BLOCK; EACH OF SAID CAVITIES INCLUDING ARADIALLY-INNER, SOCKETRECEIVING-OPENING EXTENDING BETWEEN SAID OPPOSITEFACES TO ACCOMMODATE SAID SOCKET WITH THE SOCKET MAJOR DIMENSIONEXTENDING TANGENT TO THE CIRCLE PASSING THROUGH SAID PIN-TABS, AND ANADJACENT, RADIALLY-OUTER TROUGH TO ACCOMMODATE SAID FERRULE, SAID TROUGHEXTENDING RELATIVELY TO THE EDGE OF SAID BLOCK TO PROVIDE AN OPENING FORTHE EMERGENCE OF THE WIRE GRIPPED BY SAID FERRULE IN THE IMMEDIATEVICINITY OF SAID CAVITY, SAID TROUGH EXTENDING TO SAID BLOCK EDGES IN APATH IN WHICH IS DOES NOT PASS MORE CLOSELY TO ANY ADJACENT TERMINALCAVITY WITHIN THE PERIPHERAL LIMITS OF SAID BLOCK THAN THE SPACINGBETWEEN ADJACENT TERMINALS, SAID INTERMEDIATE WEB BEING BENT TO FORM ANACUTE ANGLE BETWEEN SAID FERRULE AND CONTACT SOCKET SO THAT SAID FERRULEOCCUPIES A LEVEL IN SAID TROUGH WITHIN THE LENGTH OF SAID CONTACTSOCKET.